>I would imagine that a vacuum pump based on amperian forces would be impractical. You would go from extreme pressure to a vacuum condition in microseconds.

Thats whats so good about at! An evacuation pulse causes a near vacuum, and right away extreme high voltage/energy fusing potentials are appied. Not without precident, they sometimes start big turbojets with small explosions.

Losses are lower, that is the ion currents are more reactive and less resistive at high energies. Also the resonances, the tuning of the plasma is lower at higher energies due to stronger magnetic fields. A series of precision timed high energy pulses may be the only way to get the system going, because losses would be too high to let the system gradualy converge.

Therefore the need for accurate simulation and modeling.

> How good the vacuum might be is a matter for very fast gauging that can also take on huge overpressures and survive.

I would gauge pressure by the impulse response, and by RF probing of the plasma, which is what realy matters anyways

Having seen the diagrams for the water thruster and fusion reactor at the reference I posted, I don't doubt that. What I wonder about is the "K" factor, which they say is 7 for metals and around 1000 for water (and probably more for plasma). Is this K factor due to coulomb repulsion? Relativistic electron magnetic fields? It makes a very big difference in the utility and application of the high current plasma.